Abstract
Alumina nanoparticles with various shapes have been loaded into water to accelerate the freezing phenomena within closed cavity. The mathematical model contains unsteady conduction equation in the existence of unsteady source terms for phase changing. In this model, three properties of NEPCM are involved and for calculating those parameters, single phase approximation has been utilized. By using FEM, outputs for impact of shape and volume of nanoparticles have been reported. Also, the method was verified by comparing the outputs with the previous data. Increasing the volume of nanoparticles to twice the range makes the needed time decrease by about 13.82%. When phi=0.02, replacing nanoparticles with m=8.6 instead of m=4.8 makes freezing time decrease by about 3.92%.